You really have 2 separate equations to solve here:
1) 5(x-1) = - 20 => 5x - 5 = -20 => 5x = -15 => x = -3
2) 3y = -15 => y = -5
The pie grid is out of 100%. When you add 10%, 25% and 40% you get 75%. Subtract 100% and 75% and you get the answer of 25%.
Um........its confusing to explain sorry
Answer:
the value of c(30) is 21.2, which represents the customers final cost of $21.20
Step-by-step explanation:
d
20 books per box and x number of boxes.
To write an equation you have to figure out what variable you are solving for, which is x. Then you see what x is, which is the number of boxes. Finally you figure out what it takes from the given no. to get to the answer, x.
y = no. of books
x = y/20